1. Field of the Invention
The present invention relates to a method and system for determining a subject interest level to media content, and specifically to the level of interest a subject expresses in content of an image on a display. More particularly, the invention relates to a method and system for non-intrusively detecting how interested a subject is to media content (e.g., the content originating from broadcast or cable TV, the web, a computer application, a talk, a classroom lecture, a play, etc.).
2. Description of the Related Art
Information technologies have become quite efficient at data transmission. However, users are not interested in data per se, but instead want data that is useful for a particular task. More specifically, people desire interesting information suited to a particular topic, problem, etc. The importance of providing interesting information in communication has been noted by various philosophers and scientists, including Grice, H. P. Logica and Conversation, in: P. Cole & J. Morgan (Eds.), Syntax and Semantics 3: Speech Acts, pp. 41–58, (New York: Academic Press, 1967) who urged that speakers must make their communication relevant to the listener if communication is to be successful.
The problem of determining whether data is interesting to a receiver has been addressed in different ways within different media. In interpersonal communication, a listener provides a speaker with verbal and non-verbal feedback (e.g., cues) that indicates the listener's level of interest.
In many mass media, such as television, multiple channels that offer some variety of information are provided, and people receiving the information select from the available information whatever seems most interesting. Then, people's selections are measured (e.g., typically by sampling a small segment of viewers such as by the Nielsen ratings or the like), so that more interesting and new (potentially interesting) content can be made more available, and content that is not interesting can be made less available.
The interpersonal means of interest level detection has an advantage over the typical mass media means in that in the interpersonal medium, interest level detection occurs in real time, within a single exchange of information rather than between a plurality of exchanges of information. The speaker can introduce information, assess the listener's interest in the information and then consider the listener's interests when presenting subsequent information. Thus, the speaker can tailor the subsequent information depending upon the listener's perceived interest.
Mass media technologies typically rely on less immediate feedback (e.g., again through ratings or the like of a small population sample, oftentimes not proximate to the original presentation of the information). A drawback to this procedure is that people have to search through information, looking for something interesting, only to discover that sometimes none of the available information is interesting. Currently, there are no methods or systems for assessing and communicating a person's level of interest by passively observing them, especially in a mass media technology environment.
It is noted that some conventional systems and methods exist for assessing a mental state of a person, but these systems and methods have certain drawbacks.
In one conventional system, a device is provided for estimating a mental decision. This estimate is performed by monitoring a subject's gaze direction along with the subject's EEG, and by processing the output signals via a neural network to classify an event as a mental decision to select a visual cue. Thus, the device can detect when a subject has decided to look at a visual target. The EEG is detected via skin sensors placed on the head.
In a second conventional method and system, a person's emotional state is determined remotely. Such a technique is performed by broadcasting a waveform of predetermined frequency and energy at an individual, and then detecting and analyzing the emitted energy to determine physiological parameters. The physiological parameters, such as respiration, blood pressure, pulse rate, pupil size, perspiration levels, etc. are compared with reference values to provide information indicative of the person's emotional state.
In yet another conventional system, a method is provided for evaluating a subject's interest level in presentation materials by analyzing brain-generated event related potential (ERP) and/or event related field (ERF) waveforms. Random audio tones are presented to the subject followed by measurement of ERP signals. The level of interest is computed from the magnitude of the difference of a baseline ERP signal and an ERP signal during a task (e.g., during a video presentation). The difference is correlated to the interest level which the subject expressed by filling out a questionnaire about the video presentations. ERP measurement requires scalp sensors and although it has been suggested that using EMF signals would allow such a technique to be performed non-intrusively, no evidence or practical implementation is known which makes possible such non-intrusive activity.
In other work, it has been determined that perplexed behaviors of a subject using a word processor resulted in head motion changes more than facial expression changes. Dynamic programming is employed to match head motion with head motion templates of the following head gestures: nod, shake, tilt, lean backwards, lean forwards, and no movement. When the subject (user) displays appropriate head gestures, it can be detected when the person is perplexed.
However, in the above technique, only perplexed behaviors, not a general level of interest, was detected.
Other experiments have been performed which indicate that people naturally lean forward when presented positive valence information. In one experiment, a mouse with a trackpoint was used and the forward pressure on the trackpoint was measured and then correlated with the valence level of presented information.
No methods or systems exist for assessing and communicating a person's level of interest in real-time by passively observing them, especially in a mass media technology environment.